Diffuser



FIG. 1 is a perspective view of a diffuser according to our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a right side elevation view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a left side elevation view thereof.

In the drawings, the broken lines depit portions of the diffuser that form no part of the claimed design. 

CLAIM I claim the ornamental design for a diffuser, as shown and described. 